I read The Bestseller Code a couple of months ago, snagging a bargain copy on eBay. It's a pre-publication advance reading copy, which still has the pencil scribblings of some reviewer (presumably not you, Brian) in the margins to serve as reminders for their review of the guide—which I hope was more polite than the scatological remarks they failed to erase.
As a send-me-to-sleep bedtime book, it was excellent! The main things that I learned from reading it, were that best-selling books favour the use of contractions, such as
they'd or
we've, rather than saying
they had and
we have.
The other really surprising fact that the authors unearthed from trawling the data of bestsellers, was what a minuscule percentage descriptions of sexual activity take up in novels that aren't part of the erotic genre. It's the same with other raunchy subject areas like rock and roll and drug taking. These percentages startled me, as I was thinking of sexing-up the detective protagonist of my series of Cornish crime novels, perhaps giving him some bad habits.
In measuring the presence of sex, drugs and rock and roll, they found that in 5,000 novels, 500 of which were bestsellers, and concentrating on 500 different themes, that the proportion taken up by sex amounted to a thousandth of a percent.
Sex: 0.001%
Drugs: 0.003%
Rock and Roll: 0.001%
When they measured
only bestsellers, the proportion of sexual content dipped to 0.0009%.
Erotica/sex stories do sell, of course, but only in a niche market. The 50 Shades series is a rare example of a story that broke through to become a bestseller.
I might have to leave my fictional detective as a celibate, herbal tea-drinking hermit who listens to New Age music!
(Rumours that my hero is autobiographical are open to speculation....)